Vapor Phase of Thermally Unstable Sm, Eu, Yb Bromides

Abstract

Vaporization of thermally unstable SmBr3, YbBr3, SmBr2, EuBr2, and YbBr2 is investigated by the high temperature mass spectrometry. It is found that the composition of vapor phase changes in the course of vaporization due to thermal decomposition of tribromides and disproportionation of dibromides. The neutral (Ln, Br, Br2, LnBr, LnBr2, LnBr3, Ln2Br4, Ln2Br5, and Ln2Br6) and charged (Br–, LnBr3 –, LnBr4 –) species are present in vapor at various vaporization stages. Eventually for each sample studied the vaporization approaches steadiness when the LnBr2 molecules are predominant in the vapor.